【作者】 任伟；

【导师】 房大中；

【作者基本信息】 天津大学 ， 电力系统及其自动化， 2009， 博士

【摘要】 近年来,随着跨区域电网的建设,电网结构日趋复杂。伴随着超高压直流输电与超高压远距离交流输电的并联运行,以及各种新技术的使用,系统的运行控制复杂,稳定问题严重。为维护电力系统的第二三道防线,不少电网建立了规模庞大的电网安全稳定系统,以实现全网紧急控制的及时实施。制定合理有效的紧急控制措施是本文研究的核心内容。暂态稳定紧急控制和优化算法近年来吸引了不少工程技术人员的研究兴趣,并取得了一定进展。但由于问题本身的离散性和工程涉及面广,该研究领域的研究工作和实际工程应用尚有不少距离。本文在充分研究工程背景的基础上,对各种研究方法进行了综述和比较,提出基于暂态能量的控制方法,力求理论联系实际,以解决实际的工程问题。文章主要内容包括:1.全面介绍了电网安全稳定控制系统的组成和功能,作为紧急控制的实现平台,阐明了在规模不同的电网上的工作模式,对离线决策、在线预决策、实时决策的工作模式进行了综述,从电力系统数据源的角度展望了在线安全分析前景。2.提出暂态能量控制理论,从暂态能量角度对各种控制措施进行了分析;定义了暂态能量控制指标,并进行了分类;定义了能量型灵敏度,并提出应用方法。3.定义了切机控制指标和切机灵敏度。在10机39节点上的算例进行了指标和灵敏度的特点分析。对南方电网交直流西电东送通道进行了详细的分析,研究了了交直流系统并联运行方式在大扰动下的交直流相互影响模式和暂态电压与功角稳定问题,并对各种控制措施进行了分析比较,确定了切机控制的有效性。4.使用能量灵敏度确定切机顺序,使得满足暂态稳定约束的最优切机量比以往使用角度灵敏度确定的切机量更少,更为有效。在南方电网西电东送通道上的算例证明了方法的有效性和实用性。5.对区域电网的运行模式进行了分析,提出使用修正能量暂态能量函数的可行性依据。对切除措施的能量裕度进行了分析,定义了稳定轨迹的能量裕度,并分析了能量裕度的定义根据。在能量裕度的指导下快速求取满足暂稳约束的最佳切除量,减少了试探法的盲目性,降低了求取安稳策略的工作量。在广东粤东梅县地区电网上的算例证明了方法的有效性。更多还原

【Abstract】 In the recent years, with the fast building of interconnected power grid, network structure has becoming more and more complex. With the parallel operation on ultra high voltage DC transmission and AC transmission, and configuration on the devices utilizing new technology widely, the operation of modern power system presents very complex and shows serious stable problem. Today security and stability control system (SSCS) has been applied to power grid widely in order to safeguard the reserve defense line of power system and to ensure the emergency control measures trigger in time. Fast evaluating, confirming and optimizing emergency control method are of great importance to the improvement on power grid security and the loss reduction in case of faults.Currently transient stability-constrained emergency control and optimization have been under intensive investigation, with some progress being made on these research fields. As yet few scheme has reached a practical level due to the inherent discreteness and widely engineering related. In this thesis, several control performance index and its sensitivity based on transient energy have been proposed, considering the background of engineering technology. Moreover, many research methods previous reported have been discussed and reviewed. The contents and creative points of this thesis are as follow1. As the implementation platform of emergency control, the security and stability control systems are introduced in detail. The working modes of SSCS are enlightened according to different power system scale and size. In addition, the decision-making modes of offline, on-line preventive and real time are also discussed and prospected from the point of view of the development of data sources in power system.2. The transient energy based control theory is proposed, and the control measures are discussed from this theory. And the energy-type performance and sensitivity are defined. Furthermore, the application methods based on the novel index are also presented.3. The control performance index and sensitivity for generator tripping are defined. The case examples on New England test power system show the basic properties of the novel indices. On the background of DC and AC power transmissions on South China Power Grid, the transient voltage problem following synchronism stability problem are investigated intensively. Furthermore, the interaction of AC and DC transmissions is discovered clearly. Then the effectiveness and practicality of the generator tripping control are discussed and emphasized.4. Compared with angle index, the more effective generation drop measures or the least drop power can be obtained by the energy-type sensitivity index, which can obtain the better transient stability constrained emergency control measures and get the loss reduction in case of faults. The case examples on South China Power Grid show that the proposed approach is practical and effective.5. Based on the properties of the operation mode on regional power network, the feasibility and foundations of Corrected Transient Energy Function are explained in order to apply the CTEF method to regional power grid. A new stability margin by different drop power has been defined, considering the constant of corrected transient energy function (CTEF). The definition of stability margin for the stable case of the first swing is discussed in detail. From the definition procedure and regularity of stability margin, the estimated drop power by generation tripping control can be obtained from only two simulation process. The case examples on the MeiZhou power grid in GuangDong show that the proposed approach reduces the heavy workload using the traditional method of trials and errors to find a suitable unit combination to drop.更多还原